Funding is requested for an 800 MHz NMR CryoProbe to support the research of a group of NIH, NSF and DOE funded scientists at UCLA, this probe will be used to help solve the structures and dynamics of proteins, nucleic acids, DNA-protein, RNA-protein, and protein-protein complexes proposed for investigation by the major users. The research projects of the six major users are described with the following titles: (1) NMR studies of proteins and their complexes (Clubb), (2) Structural studies of nucleic acids and complexes (Feigon), (3) SAM domain structure and function (Bowie), (4) Structure/function of HIV-1 Vpr and HHR23A associated cellular proteins (Chen), (5) Regulation of phage lambda site-specific DMA recombination by Xis and Fis (Johnson), and (6) Chaos Control and Sensitivity Enhancement in Biomolecular NMR (Lin). The probe will be located in the UCLA-DOE NMR Technology Center. It will significantly improve the sensitivity of the Center's single 800 MHz spectrometer enabling a greater number of projects to benefit from access to this high-field instrument. [unreadable] [unreadable]